Playing Sound with Javascript

sound_maker.js

class SoundMaker {
  constructor() {
    this.context = new AudioContext();
    this.oscillator = new Oscillator(this.context);
    this.gain = this.context.createGain();
    this.volume = new Volume(this.context, this.gain);
  }

  start() {
    this.oscillator.connect(this.gain);
    this.gain.connect(this.context.destination);
    this.oscillator.start();
  }

  setNote(frequency, type) {
    this.setFrequency(frequency);
    this.setType(type);
  }

  setFrequency(frequency) { this.oscillator.setFrequency(frequency); }

  setType(type) { this.oscillator.setType(type); }

  down(x) { this.volume.down(x); }

  up(x) { this.volume.up(x); }

  mute(mute = true) { this.volume.mute(mute); }

  stop() { this.oscillator.stop(); }
}

class Oscillator {
  constructor(context) {
    this.context = context;
    this.oscillator = context.createOscillator();
  }

  // hertz
  setFrequency(frequency = 440.0) {
    this.oscillator.frequency.setValueAtTime(frequency, this.context.currentTime);
  }

  setType(type = "sine") {
    const validTypes = ["sine", "square", "sawtooth", "triangle"];

    if (!validTypes.includes(type)) return;

    this.oscillator.type = type
  }

  connect(object) {
    this.oscillator.connect(object);
  }

  start() {
    this.oscillator.start(0);
  }

  // destructive, won't be able to start it again
  stop() {
    this.oscillator.stop();
  }
}

class Volume {
  constructor(context, gainNode) {
    this.gainNode = gainNode
    this.gain = gainNode.gain;
    this.context = context;
  }

  mute(mute = true) {
    if (mute) {
      this.gainNode.disconnect(this.context.destination);
    }
    else {
      this.gainNode.connect(this.context.destination);
    }
  }

  down(x = 1) {
    this.gain.exponentialRampToValueAtTime(
      0.00001, this.context.currentTime + x
    )
  }

  up(x = 1) {
    this.gain.exponentialRampToValueAtTime(
      0.5, this.context.currentTime + x
    )
  }
}

usage.js

let maker = new SoundMaker();

// make sure you set your volume to low before proceeding
maker.start();
maker.setNote(261.6, "sine");
maker.mute();
maker.mute(false);
maker.setNote(174.6, "square");
maker.setNote(1109, "sawtooth");
maker.setNote(87.31, "triangle")
maker.mute();